Abstract: Objective: The effect of nobiletin on the body weight, serum lipids and liver of rats exposed to a high-fat diet were investigated. Methods: Totally 56 male SD rats were randomly divided into seven groups: normal control group, highfat diet control group, positive control groups (orlistat and fenofibrate), and low-, middle- and high-dose nobiletin groups (high-fat diet + 0.02%、0.04%、0.08% nobiletin). The rats in the normal control group were fed normal diet, while the remaining groups were fed high-fat diet plus the corresponding drugs for six weeks. Then serum lipid parameters, body weight, body fat weight, organ weight to body weight ratios and liver histopathology were examined. Results: Nobiletin could inhibit body weight gain induced by high-fat diet in rats, reduce Lee’s index, food utilization rate and fat to body weight ratio, and decrease serum total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) levels with the fastest rate of decrease being observed for TG. Compared with the high-fat control group, liver index and serum glutamic oxalacetic transaminase (AST) and alanine transaminase (ALT) activities in the nobiletin treatment groups were decreased, and fatty degeneration of the liver was improved. Conclusion: Nobiletin can reduce serum lipids and prevent obesity and fatty liver.

Key words: nobiletin, high-fat diet, rats, obesity prevention, hypolipidemic, prevention of fatty liver